Essays on Mankind and Political Arithmetic

by Sir William Petty

OBSERVATIONS UPON THE DUBLIN BILLS OF MORTALITY, 1681: AND THE STATE OF THAT CITY.

The observations upon the London bills of mortality have been a new light to the world, and the like observation upon those of Dublin may serve as snuffers to make the same candle burn clearer.

The London observations flowed from bills regularly kept for near one hundred years, but these are squeezed out of six straggling London bills, out of fifteen Dublin bills, and from a note of the families and hearths in each parish of Dublin, which are all digested into the one table or sheet annexed, consisting of three parts, marked A, B, C; being indeed the A, B, C of public economy, and even of that policy which tends to peace and plenty.

Observations upon the Table A.

1. The total of the burials in London (for the said six straggling years mentioned in the Table A) is 120,170, whereof the medium or sixth part is 20,028, and exceeds the burials of Paris, as may appear by the late bills of that city.

2. The births, for the same time, are 73,683, the medium or sixth part whereof is 12,280, which is about five-eighth parts of the burials, and shows that London would in time decrease quite away, were it not supplied out of the country, where are about five births for four burials, the proportion of breeders in the country being greater than in the city.

3. The burials in Dublin for the said six years were 9,865, the sixth part or medium whereof is 1,644, which is about the twelfth part of the London burials, and about a fifth part over. So as the people of London do hereby seem to be above twelve times as many as those of Dublin.

4. The births in the same time at Dublin are 6,157, the sixth part or medium whereof is 1,026, which is also about five-eighth parts of the 1,644 burials, which shows that the proportion between burials and births are alike at London and Dublin, and that the accounts are kept alike, and consequently are likely to be true, there being no confederacy for that purpose; which, if they be true, we then say—

5. That the births are the best way (till the accounts of the people shall be purposely taken) whereby to judge of the increase and decrease of people, that of burials being subject to more contingencies and variety of causes.

6. If births be as yet the measure of the people, and that the births (as has been shown) are as five to eight, then eight-fifths of the births is the number of the burials, where the year was not considerable for extraordinary sickness or salubrity, and is the rule whereby to measure the same. As for example, the medium of births in Dublin was 1,026, the eight-fifths whereof is 1,641, but the real burials were 1,644; so as in the said years they differed little from the 1,641, which was the standard of health, and consequently the years 1680, 1674, and 1668 were sickly years, more or less, as they exceeded the said number, 1,641; and the rest were healthful years, more or less, as they fell short of the same number. But the city was more or less populous, as the births differed from the number 1,026, viz., populous in the years 1680, 1679, 1678, and 1668, for other causes of this difference in births are very occult and uncertain.

7. What hath been said of Dublin, serves also for London.

8. It hath already been observed by the London bills that there are more males than females. It is to be further noted, that in these six London bills, also, there is not one instance either in the births or burials to the contrary.

9. It hath been formerly observed that in the years wherein most die fewest are born, and vice versa. The same may be further observed in males and females, viz., when fewest males are born then most die: for here the males died as twelve to eleven, which is above the mean proportion of fourteen to thirteen, but were born but as nineteen to eighteen, which is below the same.

Observations upon the Table B.

1. From the Table B it appears that the medium of the fifteen years’ burials (being 24,199) is 1,613, whereas the medium of the other six years in the Table A was 1,644, and that the medium of the fifteen years’ births (being in all 14,765) is 984, whereas the medium of the said other six years was 1,026. That is to say, there were both fewer births and burials in these fifteen years than in the other six years, which is a probable sign that at a medium there were fewer people also.

2. The medium of births for the fifteen years being 984, whereof eight-fifths (being 1,576) is the standard of health for the said fifteen years; and the triple of the said 1,576 being 4,728, is the standard for each of the ternaries of the fifteen years within the said table.

3. That 2,952, the triple of 984 births, is for each ternary the standard of people’s increase and decrease from the year 1666 to 1680 inclusive, viz., the people increased in the second ternary, and decreased from the same in the third and fourth ternaries, but re-increased in the fifth ternary beyond any other.

4. That the last ternary was withal very healthful, the burials being but 4,624, viz., below 4,728, the standard.

5. That according to this proportion of increase, the housing of Dublin have probably increased also.

Observations upon the Table C.

1. First, from the Table C it appears, 1. That the housing of Dublin is such, as that there are not five hearths in each house one with another, but nearer five than four.

2. That in St. Warburgh’s parish are near six hearths to a house. In St. John’s five. In St. Michael’s above five. In St. Nicholas Within above six. In Christ Church above seven. In St. James’s and St. Katherine’s, and in St. Michan’s, not four. In St. Kevin’s about four.

3. That in St. James’s, St. Michan’s, St. Bride’s, St. Warburgh’s, St. Andrew’s, St. Michael’s, and St. Patrick’s, all the christenings were but 550, and the burials 1,055, viz., near double; and that in the rest of the parishes the christenings were five, and the burials seven, viz., as 457 to 634. Now whether the cause of this difference was negligence in accounts, or the greaterness of the families, &c., is worth inquiring.

4. It is hard to say in what order (as to greatness) these parishes ought to stand, some having most families, some most hearths, some most births, and others most burials. Some parishes exceeding the rest in two, others in three of the said four particulars, but none in all four. Wherefore this table ranketh them according to the plurality of the said four particulars wherein each excelleth the other.

5. The London observations reckon eight heads in each family, according to which estimation, there are 32,000 souls in the 4,000 families of Dublin, which is but half of what most men imagine, of which but about one sixth part are able to bear arms, besides the royal regiment.

6. Without the knowledge of the true number of people, as a principle, the whole scope and use of the keeping bills of births and burials is impaired; wherefore by laborious conjectures and calculations to deduce the number of people from the births and burials, may be ingenious, but very preposterous.

7. If the number of families in Dublin be about 4,000, then ten men in one week (at the charge of about £5 surveying eight families in an hour) may directly, and without algebra, make an account of the whole people, expressing their several ages, sex, marriages, title, trade, religion, &c., and those who survey the hearths, or the constables or the parish clerks (may, if required) do the same ex officio, and without other charge, by the command of the chief governor, the diocesan, or the mayor.

8. The bills of London have since their beginning admitted several alterations and improvements, and £8 or £10 per annum surcharge, would make the bills of Dublin to exceed all others, and become an excellent instrument of Government. To which purpose the forms for weekly, quarterly, and yearly bills are humbly recommended, viz.